1. Field of the Invention
The present invention relates to an improved underlay for use in installing a tile floor of a shower. In particular, the invention relates to novel, universal pieces of planar material which are readily positioned about the drain of a shower floor and provide the proper slope for the pan of the tile shower installation.
2. State of the Art
Building codes generally specify that a pan be placed on the floor, with mortar and tile being laid over the pan. The purpose of the pan is to direct any water seeping by the tile to the drain rather than into the floor beneath the shower. To accomplish its purpose, the pan must slope to the drain which is generally positioned at the center of the shower floor. The general practice is for the mason to place sand on the floor and to slope the sand from the outer edges of the shower stall toward the drain. The pan is then placed on the sand underlayment. Laying of the sand underlayment is time consuming, and in many installations, especially those done by do-it-yourself masons, the pan gets placed directly on the floor with no slope.
In the prior patent art there are disclosures of shower units in which the base of the unit forming the floor of the shower is prefabricated to set on the support structure such as the sub-floor of the shower stall. These units are made of metal or plastic and of a predetermined sized. The units cannot be reduced in size, and thus there is no flexibility for custom designed and sized shower installations. These units further have integral floors and are not adapted to have tile laid on the floors. Representative examples of such patent art are U.S. Pat. Nos. 1,766,125; 2,437,068; 3,800,335; 3,895,398; and 4,423,528.
A prefabricated floor module which has roughly textured inside surfaces to which tile can be laid is disclosed in U.S. Pat. No. 4,557,004. The unit is integrally formed from plastic materials. It is formed to a definite, preset size and cannot be changed. There is no flexibility for custom designed and sized shower installations. The floor module is cumbersome and awkward to use as well as costly to make and use.
3. Objectives
A principal objective of the present invention is to provide a segmented underlay for use in installing a tile floor of a shower wherein the underlay comprises inexpensive planar members which are laid side-by-side on the sub-floor of the shower stall.
A particular objective of the present invention is to provide such a segmented underlay in which each member used in making the underlay is identical to the other members so as to reduce cost of manufacturing and eliminate the need for stocking multiple sets of members in different sizes and shapes.
An additional objective of the present invention is to provide such a segmented underlay in which each member when laid on the sub-floor will provide an upper surface which slopes toward the drain, and in combination with the other members of the underlay forms a uniform surface upon which the pan of the shower floor is supported.
A further objective of the present invention is to provide such a segmented underlay in which each of the members can be cut using conventional tools to any desired size, and wherein a plurality of markings are applied to the surface of the member to aid in cutting the member to such desired size.